Serum uric acid levels and hormone therapy type: a retrospective cohort study of postmenopausal women.

OBJECTIVE: Serum uric acid levels increase in postmenopausal women, but decrease when hormone therapy (HT) is administered. No study has, however, evaluated the effects of different types of HT on serum uric acid levels. We therefore examined whether estrogen therapy (ET), estrogen plus progestogen therapy (EPT), and tibolone use affected serum uric acid levels in this population. METHODS: We performed a retrospective cohort study of postmenopausal women. From 2005 to 2015, postmenopausal women who had undergone blood uric acid-level testing at least twice were enrolled. Participants were grouped according to HT regimen: ET, EPT, or tibolone. The nonhormone therapy group did not receive HT. Differences in serum uric acid levels were examined in each group. Our analysis was adjusted to accommodate different follow-up intervals for individual participants. Multiple variables were adjusted using the Tukey-Kramer method. Age, body mass index, hypertension, diabetes mellitus, dyslipidemia, estimated glomerular filtration rate, alcohol consumption, smoking status, and comedications were also adjusted. RESULTS: After adjusting for multiple variables, the serum uric acid level increased to 0.87 ±â€Š0.27 mg/dL (least squares mean ±â€Šstandard error) in the nonhormone therapy group, and serum uric levels in the EPT group were found to be significantly lower (-0.38 ±â€Š0.29 mg/dL, P < 0.001). The serum uric acid levels in the ET and tibolone groups did not, however, differ significantly from the nonhormone therapy group level. CONCLUSIONS: We attribute our findings to the effects of progestogen, rather than estrogen.

Preparation and application of a new modified liquid chromatographic chiral stationary phase based on (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid.

As an effort to improve the chiral recognition efficiency of a previously reported chiral stationary phase (CSP) based on (+)-(18-Crown-6)-2,3,11,12-tetracarboxylic acid, a new CSP was prepared by simply replacing the amide N-H hydrogens of the tethering groups of the old CSP with methyl groups. The new CSP was superior to the old one in the resolution of racemic primary amines. However, in the resolution of alpha-amino acids and amino alcohols, the new and the old CSPs were complementary with each other. The elution orders on the new CSP were sometimes opposite to those on the old one. Consequently, the chiral recognition mechanism on the new CSP was presumed to be different from that on the old one. The chiral recognition behavior of the new CSP were investigated with four selected analytes and found to be dependent to some extent on the content of organic and acidic modifiers in aqueous mobile phase and the column temperature.